Dishwasher apparatus

ABSTRACT

A DISHWASHER THAT INCLUDES A LIQUID CONDUIT AND A ROTATABLE SPRAY ARM AN ARTICLE HOLDING RACK SPACED FROM THE SPRAY ARM IN WHICH A PORTION OF THE LIQUID THAT IS UNDER PRESSURE WITHIN THE SPRAY ARM IS PERMITTED TO ESCAPE TO THE OUTSIDE OF THE ARM, AND IN WHICH INTERCEPTING AND PROJECTING MEMBERS ARE PROVIDED FOR DIRECTING THIS ESCAPING LIQUID FIRST ALONG THE OUTER SURFACE OF THE SPRAY ARM AND THEN TOWARD THE ADJACENT RACK AND ARTICLES SUCH AS DISCHES THEREIN.

p 20, 1971 w. F. ROBANDT u, ETAL 3,605,770

DI SHWASHER APPARATUS Filed April 15, 1970 LZH I] I B n 2 N 2| g e 23 2 20 7f) 20 26 I I. ll l l8 E I I U I5 |5 ii I? T '3 l4 l2 MOTOR PUMP UNIT FIGZ INVENTORS. WILLIAM F. ROBANDT II RAYMOND W. SPIEGEL BY 4W5 7m due.

IATTORNEYS.

United States Patent Olfice 3,605,770 Patented Sept. 20, 1971 3,605,770 DISHWASHER APPARATUS William F. Robandt H, St. Joseph, and Raymond W. Spiegel, Stevensville, Mich., assignors to Whirlpool Corporation Filed Apr. 15, 1970, Ser. No. 28,648 Int. Cl. B08b 3/02 U.S. Cl. 134179 9 Claims ABSTRACT OF THE DISCLOSURE A dishwasher that includes a liquid conduit and a rotatable spray arm and an article holding rack spaced from the spray arm in which a portion of the liquid that is under pressure within the spray arm is permitted to escape to the outside of the arm, and in which intercepting and projecting members are provided for directing this escaping liquid first along the outer surface of the spray arm and then toward the adjacent rack and articles such as dishes therein.

SUMMARY OF THE INVENTION BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary view partially in section of a dishwasher apparatus embodying the invention.

FIG. 2 is a fragmentary plan view of a portion of the spray arm in the area surrounding its axis of rotation.

FIGS. 3 and 4 are views similar to FIG. 2 but each illustrating a further embodiment of the invention.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS In the apparatus illustrated in the accompanying drawings the dishwasher comprises a customary tub 10, an article or dish retaining rack 11 therein and a motor and pump unit 12 for pumping washing liquid, either detergent liquid or rinse liquid, under pressure in the customary manner.

Leading upwardly from the unit 12 is a liquid conduit means 13 in the form of a vertically arranged liquid conveying pipe. Rotatably mounted on this pipe in a position beneath the rack 11 is a spray arm 14 that is supplied with liquid under pressure from the motor-pump unit 12 by way of the vertical pipe 13 and openings 15 therein within the confines of the spray arm 14.

The liquid under pressure from the unit 12 flows through the openings 15 and through the hollow interior 16 of the arm in the customary manner. From this interior 16 the liquid under pressure is sprayed upwardly onto articles (not shown) retained within the rack 11. This upward spray is provided by the customary spray openings (not shown) with also impart rotation to the arm in the customary manner by the reaction of the emerging liquid jets.

The arm 14 is rotatably mounted on the vertical pipe 13 by a mounting means including an upwardly extending annular bottom flange 17 on the bottom of the spray arm 14 and a downwardly projecting top flange 18 on the top of the spray arm.

The top flange 18 is spaced from the adjacent portion of the liquid conduit means pipe 13 to provide an annular leakage space 19 through which liquid flows as indicated by the arrows 20 to the exterior of the spray arm 14. This flow space 19 is on the side of the arm 14 that is adjacent the rack 11.

The apparatus also includes intercepting means here embodied in a cross member 21 and specifically a cap on the end of the liquid pipe 13 for maintaining spray arm 14 positioned on pipe 13 and for intercepting the emerging liquid portion 20 and directing it adjacent the outer surface side 22 of the spray arm that is adjacent the rack 11. This intercepting means cap 21 has a flat bottom surface 23 adjacent the arm 14 so that the liquid flow 20 will be substantially equal around the axis of rotation 24 of the arm.

The dishwasher apparatus of this invention also in cludes projecting means 25 for intercepting the liquid indicated at 20 and projecting it toward the rack 11 as indicated by the upwardly extending arrows 26. In the embodiments of FIGS. 1 and 2 this projecting means is in the form of an upward extending protuberance on the upper surface of the spray arm 14 and specifically a circular ridge that is substantially concentric to the axis of rotation 24 and the top flange 18. This ridge 25 is located radially beyond the cap 21 so that the upwardly projected liquid 26 will not contact the bottom surface 23 of the cap.

In the embodiment of FIG. 3 the spray arm 114 is also provided with a circular ridge but here the ridge is eccentric to the axis of rotation 124 so as to produce a sweeping back and forth action of the upwardly projected liquid that impinges on the ridge 125.

In the embodiment of FIG. 4 the spray arm 214 is provided with spaced sets of arcuate ridges 225 and 227 with the ridges in one set 225 being spaced a greater distance from the axis of rotation 224 than are the ridges 227 of the other set. As can be seen in FIG. 4 each of the ridges in this embodiment extend arcuately so that the ridges 225 describe a circle and the ridges 227 describe a circle of smaller diameter.

In the preferred embodiments the spray arms 14, 114 and 214 comprise any sheet material that can be shaped as indicated. Preferably this sheet material is either metal or a rigid plastic.

In the embodiment shown in FIG. 1 the cap 21 may be provided with a central aperture aligned with pipe 13 to allow a jet of water to be projected upwardly to an upper spray arm (not shown). The concept of projecting a column of liquid to an upper spray arm is fully disclosed in US. Pats. 3,180,348 and 3,444,870 which are assigned to the assignee of this application.

In the structure of this invention the liquid that normally tends to leak between the rotatable spray arm and the liquid conduit pipe or similar supporting structure as identified at 13 is used to provide an additional liquid spray on the articles such as dishes in the rack 11. Thus this invention not only provides an additional spray to aid in cleaning the articles but also permits the omission of liquid seals that are normally employed in order to avoid this leakage. Also the top retaining cap illustrated at 21 is used to retain spray arm 14, to close the upper end of the pipe 13 or alternately form a projecting nozzle, and to provide a liquid directing surface 23 for predetermining the direction of liquid flow as illustrated at 20.

Having described our invention as related to the embodiments shown in the accompanying drawings, it is our intention that the invention be not limited by any of the details of description, unless otherwise specified, but

rather be construed broadly within its spiritand scope as set out in the appended claims.

We claim:

1. A dishwasher apparatus, comprising: a liquid conduit; a hollow spray arm; an article retaining rack spaced from said arm; means for rotatably mounting said spray arm on said conduit, said means including a liquid flow space between said conduit and arm on the side thereof adjacent said rack, said flow space thereby providing an outlet for a minor portion of said liquid to the exterior of said arm; intercepting means for intercepting said liquid portion and directing it adjacent the outer surface side of said arm that is adjacent said rack; and projecting means for projecting said liquid portion from said outer surface side toward said rack.

2. The apparatus of claim 1 wherein said intercepting means comprises a cross member having a liquid intercepting surface portion spaced from said spray arm surface side.

3. The apparatus of claim 2 wherein said cross member comprises a spray arm retaining cap on the end of said conduit that is adjacent said rack.

4. The apparatus of claim 1 wherein said projecting means comprises a protuberance on said outer surface side of the spray arm and extending toward said rack.

5. The apparatus of claim 1 wherein said intercepting means comprises a cross member having a liquid intercepting surface portion spaced from said spray arm surface side, said projecting means comprises a protuberance on said outer surface side of the spray arm and extending toward said rack and located radially beyond said cross member.

6. The apparatus of claim 5 wherein said spray arm surface side comprises a sheet material with said protuberance comprising a part thereof.

7. The apparatus of claim 5 wherein said spray arm has an axis of rotation and said protuberance is circularly arranged concentric thereto.

'8. The apparatus of claim 5 wherein said spray arm has an axis of rotation and said protuberance is circularly arranged eccentric thereto.

9. The apparatus of claim 5 wherein said spray arm has an axis of rotation and there are provided a plurality of protuberances certain of which are located varying distances from said axis.

References Cited UNITED STATES PATENTS 2,877,778 3/1959 Kirby l34183X 3,144,034 8/1964 Lyman et al. 134176 3,180,348 4/1965 Clearrnan 239-251X 3,370,869 2/1968 Dutcher 134--176X 3,444,870 5/1969 Lyman l34179 ROBERT L. BLEUTGE, Primary Examiner US. Cl. X.-R. 

